What is believed to be the origin of the Moon?

The widely accepted theory regarding the origin of the Moon is rooted in the idea of a massive collision. According to this hypothesis, sometimes referred to as the Giant Impact Theory, the Moon formed as a result of a colossal impact between the early Earth and a Mars-sized body often named Theia. This cataclysmic event ejected a significant amount of debris into orbit around Earth, which eventually coalesced to form the Moon.

This theory is supported by various lines of evidence, such as the similarity in isotopic compositions of Earth and lunar rocks, which suggests that the Moon was formed from material originating from Earth. Additionally, computer simulations of planetary formation and impact dynamics lend credence to this model, demonstrating that such a collision could lead to the formation of a satellite like the Moon.

Other theories, such as formation from dust in space or the collapse of a gas cloud, do not satisfactorily explain the specific characteristics and composition of the Moon. Similarly, the notion that the Moon was captured from another solar system lacks significant supporting evidence, particularly given the dynamics involved in capturing a large celestial body without losing it or altering its trajectory significantly.